Weatherproof covers are used in conjunction with electrical boxes or other housings to protectively enclose various fixtures, among other things. Such covers are particularly useful to afford ready access to exterior electrical outlets while protecting them from the weather. Accordingly, we will describe the present invention in that context.
The typical electrical outlet box is generally rectangular and closed on five sides. The box is recessed into or mounted exteriorly of a structure so that its open side is accessible. The box is typically sized to receive a standard duplex outlet and the outlet is secured to the box with its front face substantially flush with the open face of the box. An opening in a wall of the box permits passage of electrical leads for connecting the outlet to a suitable source of electric power.
The cover of the general type with which we are concerned here includes a cover plate which is coextensive with the open side of the box. That plate is provided with one or more apertures shaped and located so as to expose the working parts of the outlet contained in the box. The cover is usually secured in place by screws or other fasteners extending through openings in the plate and turned down into threaded holes in the box or the outlet contained therein.
The usual weatherproof cover also includes one or more spring-loaded aperture covers hinged to the cover plate which, when closed, cover and protect the electrical outlet mounted in the box when the outlet is not in use.
Prior weatherproof covers of this general type are usually relatively complex structures composed of many parts which are fairly difficult to make and to assemble. They require separate hinge pins which must be pivotally mounted to the cover plates and springs which must be engaged on those pins with their ends secured by fasteners to the plates and aperture covers respectively so that the springs will remain in proper position to bias the aperture covers to their closed positions against the plates.
Attempts have been made to simplify the construction of such covers. For example, the cover disclosed in U.S. Pat. No. 4,134,516 owned by the assignee of the present application forms hinge posts integrally with the aperture covers and biases those covers to their closed positions using a straight cantilevered spring wire. However, both the cover plate and the aperture covers of that prior unit must require relatively complex shapes with reentrant holes or overhangs to form their required hinge connections and to capture the spring wire. Therefore, those parts must be formed by a die-casting process.
Another type of prior cover disclosed in U.S. Pat. No. 3,127,048 connects the aperture cover to the cover plate using a so-called living hinge. The aperture cover is made of plastic and is formed with a thin flexible web whose edge margin is riveted to the cover plate so that the aperture cover can swing on that web toward and away from the aperture in the cover plate. A coil spring positioned between the aperture cover and the plate has one end connected by a rivet to the cover plate, while its opposite end engages over the aperture cover to bias the cover to its closed position. That prior cover is disadvantaged in that the aperture cover has to be made of a plastic capable of forming a living hinge and that material is not as rugged and durable as metal. Also, the coil spring found in that prior cover has to be riveted to the cover plate along with the aperture cover thereby increasing assembly costs.
There do exist many other types of weatherproof outlet covers which are disadvantaged in one or another respect rendering them relatively difficult to manufacture and therefore relatively expensive to purchase in the marketplace.